It is not as much as the brass that needs consideration, but the $300 custom reloading dies, that I consider too.
Yes, a 40-65 is a great round; I put a barrel on a rolling block a couple of weeks ago and have built many of them. You just run 45-70s in the sizing die. As a smokeless powder round in a strong action, it is very capable. .410 bullets; anything from 41 mag pistol bullets up to 400 grain solids.

Not sure if this helps, but.....as far as reloading dies go, because I shoot the 405G from one rifle only, I use a set of 41 Mag. dies ( $40 off fleabay ) to neck size and seat.
I use 41 Mag pistol bullets, 215gr hard cast, also 300 and 400 gr Woodleighs

Roger